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Getting the Lead Out: How Lansing, Michigan Replaced 13,500 Lead Service Lines in 12 Years

  1. Randall Roost Angie Goodman Principle Planner, Water Operations Water Quality Administrator Lansing Board of Water and Light Lansing Board of Water and Light Scott Hamelink Director, Water Operations Lansing Board of Water & Light
  2. Municipally owned utility Governed by a Board of Commissioners who set policy, approve budgets and rates Groundwater supplies two water conditioning plants that use lime- soda softening on water from 124 wells 22 MGD average daily demand providing water to 59,000 retail accounts
  3. Took ownership of all water service lines in 1927 Stopped installing LSLs in 1956 As a result of our ownership we developed a fairly accurate record of service line materials. Our service card files were kept up to date throughout. Inventoried all service line materials in 1980s, identifying as lead, copper, plastic or galvanized steel. Lead and galvanized were labeled “non-standard”. In 2004 we asked customers to self-identify LSLs. Vast majority confirmed our records. Card files were transferred to GIS.
  4. All sampling rounds have shown 90th % ile below 15ppb BWL conditioned water is high pH (9.4), moderate alkalinity (35) and hardness (98) Optimal Corrosion Control installed in 1997 Monitoring reduced to 50 locations every three years Some sampling rounds higher than others Began accelerated LSLR, public education in 2004
  5. Inventory showed about 17,000 LSLs as of the early 1990s Estimates were based on Customer Information System and GIS project Before 2004 lead service lines were replaced as needed. Developed accelerated LSLR Program, 2004 Proposed 14 year program, but the Board of Commissioners required that we target 10 years. Due to slowdown in combined sewer separation project, the anticipated completion date is now June of 2017. Current active LSLs remaining estimated at <500, 170 services with unknown materials that will be investigated to be determined if lead.
  6. Any lead service that is physically disturbed by such things as dig-ins, excavations, or leak repair. Services supplying schools, day care centers, or other identified sensitive populations as defined by the USEPA. Services where there are sample results in excess of 15 ppb. Services in the work zone of CSO replacement or street restorations. Multiple services within a compact area. Length of lead pipe present in the service line.
  7. 7 46 71 106 172 94 138 631 1632 1573 1669 1984 1974 902 596 388 329 198 210 0 500 1000 1500 2000 2500 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 Number of LSLs Replaced Number of LSLs Replaced
  8. Coordination with street projects More difficult and expensive without City Combined Sewer Overflow (CSO) Separation Project or road resurfacing Cost per service goes from $3,500 when coordinating with CSO to $6,500 without CSO. Current removal method further reduces costs. Material Costs Copper price fluctuations and the Lead Free Act have some impact but are small relative to street cut impact
  9. Meter location and ownership House on slab, service line under house, porch, or driveway Meter pit conundrum, re: ownership Crew Mobilization No partial LSL replacement mandates same-day completion, leaving us the choice of idle crew or overtime Working in the same or adjacent blocks reduces mobilization costs
  10. • Bill stuffers • Special brochures to schools, day cares, health offices • Lead information on the BWL web site • Special meetings and community events • Neighborhood meetings • Preparations for customer response FAQs • Lead Hotline • Meetings with local media
  11. The BWL hosted several community open houses at various locations around the city. 8 Stations were manned at each location: Station 1 – Information about lead service lines Station 2 – Identifying lead service lines Station 3 – Sources of lead Station 4 – What the BWL is doing Station 5 – How to protect yourself from lead Station 6 – Where your water comes from Additionally there were two other stations. One manned by staff from the county health department , and one staffed by the MDEQ.
  12. BWL does not repair LSLs…replacements only! General Customer Outreach Beginning in 2004 we developed and distributed brochures and articles in bill stuffers Conducted Open Houses at local schools and community centers Added further recommended customer precautions to our Water Quality Report As LSLR continues there is less concern from the general public LSLR Notification Letter is sent to LSL address requesting customer to contact us for an appointment. The letter explains the process Letter includes an explanation of the replacement tasks, the need for home access, BWL and customer responsibilities Meet with customer prior to or day of LSLR to explain the process, including follow-up. This helps the customer understand the details. Emergency Replacements Used only in special conditions such as service breaks. We speak with the customer on site.
  13. Access Normally just coordination but ultimately comes down to a condition of service Easements We have not sought easements and therefore must count on good customer interaction and follow- through Through Wall Bore Potential liability. Occasional disputes can be expensive
  14. Yard Restoration, non-standard installations Trees, shrubs, plantings, crawl spaces, slab foundations, porches, driveways, sheds, drywall interiors, meter access require decisions case-by-case Budget! Approximately $42 million has been spent since 2004 LSLs are replaced as a capital project (an investment into infrastructure) Rate payers share in the cost and the community has been generally supportive We are currently spending on average $3 million per year on LSLR.
  15. No Response to First Letter: Phone Call Site Visit Second Letter Sent 10 Days after Water Service is Turned Off #1 #2
  16. Prior to beginning the actual replacement of the lead service there is a substantial amount of work that must be done in advance. Scheduling of the replacement with the customer can take many iterations before an acceptable timetable can be reached. Then the utility must coordinate with local Miss-Dig to locate other utilities in the excavation areas.
  17. The process begins by shutting off the curb stop to prevent any water in the system from entering the customers premises. This is especially important to minimize the transfer of any lead particulate into the service or the customer’s household piping during the excavation of the corporation at the main.
  18. Once the curb stop has been closed the work can then be divided into two different work groups. The first work group can then enter the premises and disconnect the service from the meter assembly. The second work group can then begin the excavation process at the main to expose the corporation fitting. Excavation can be accomplished with either a backhoe or by using a vacuum excavator. The advantage of the excavator is that it can minimize the potential risk to other utilities that can be difficult to locate or may have been miss-marked.
  19. Of course there is always a lot of hand digging that must be done as well. Once the corporation is exposed the water is shut off at that location as well. It is important that the excavation of the main and the corporation be controlled to prevent any water or soils from entering the corporation or the new service once it is installed.
  20. Meanwhile inside……. While the excavation continues outside the employee inside the residence begins the disconnection of the lead service and preparing the new copper for installation. We are also replacing the water meter at the same time since we already have access to the property.
  21. One of the most important steps in preparing the new copper line to ready for installation is the sealing of the new service before it is pulled. The end of the copper pipe is covered with electrical tape. The pulling sock is then placed over the end of the copper pipe. Within the pulling sock is a small rubber ball that is pressed against the taped end of the pipe to further prevent any potential particulate from entering the new copper service during installation.
  22. Once the corporation is exposed, the excavation then moves to the curb stop. The curb stop is removed by cutting the lead line on both sides of the curb stop. Then a line is fished through the lead line from the curb stop to the inside and a 3/8” steel cable is pulled back through the service.
  23. The copper pipe is then connected to the pulling harness and the harness is connected to the steel cable. Using the backhoe, the lead service is pulled out of the ground from the basement to the curb stop.
  24. Once the copper pipe is visible in the curb stop excavation, the process stops to allow the cable to be removed from the backhoe and it is then rethreaded through the portion of the lead service line between the curb stop and the corporation. The backhoe then pulls the copper line through to the corporation excavation. From there the new copper service is attached to the corporation.
  25. Once the copper is attached to the corporation then the copper line is cut in the curb stop excavation and a new curb stop is installed. Water is then turned back on for flushing of the new service line before new water meter is connected.
  26. We then provide a set of flushing instructions to the property owner for continued flushing of the premise plumbing, with each tap flushed for 5 minutes before moving to the next tap downstream from the meter. If the customer requests it a filter will be provided to them for use for the next 3 months as an added precaution.
  27. 0 100 200 300 400 500 600 700 NumberofLeadServices Lead Service Replacement Schedule to Completion Actual Projected
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